This paper investigates the magnet as a classic “boundary object” of modern technoscientific culture. Equally at home in the nursery, dynamo, measuring instrument and navigational compass, its capricious performance nevertheless persistently eluded the powers of nineteenth century electromagnetic expertise in pursuit of the completely “permanent” magnet. Instead the untamed magnet’s resilient secularity required its makers to draw upon ancient techniques of chemical manipulation, heat treatment and maturation to render it eventually sufficiently stable in behaviour for orderly use in modern engineering. The precise methods for accomplishing this quasi-permanence were typically protected by trade secrecy – until that is Marie Sklodowska Curie’s first research publication opened up this topic for rigorous comparative research in 1898. Nevertheless, over the next quarter century her work in this field was gradually eclipsed by heavily gendered citation practices, just as the futility of attempting to accomplish complete permanency in magnets was eventually established by Sydney Evershed in the 1920s